Field of the Invention
The invention relates to an ink duct for rotary printing presses with zone-wide metering elements disposed side by side and adjustable a variable spaced distance from an ink duct cylinder, each of the metering elements having support and metering regions disposed in the axial direction of the ink duct cylinder, the support regions resting independently of one another, under spring pressure, directly or indirectly on the ink duct cylinder, and the metering regions extending in a wedgelike manner, the metering elements being pivotably supported and being coverable by an elastic foil secured to the ink duct.
In a heretofore known construction of this general type of ink duct disclosed in the published German Patent Document DE 26 48 098 C3, zone-wide metering elements are provided which have support and metering regions disposed side by side in the axial direction thereof. Because of the resilient support and hence resilient guides of the metering elements on the ink duct cylinder, any changes and fluctuations in the thickness of the ink film are eliminated. The support regions of the metering elements and the guidance therefor on the ink duct cylinder thus provide the basis or foundation for an adjustment of the metering regions which are reproducible at any time and, thus, for sensitive zonal determination of the ink gap. Differing hydrodynamic forces of the ink, sagging of the ink duct cylinder and of the ink duct, nonconcentric or faulty concentric running of the ink duct cylinder, and other deficiencies or imperfections can accordingly no longer cause any change in the ink film thickness.